Miniaturized Band Pass Filter Design Using Half Mode Substrate Integrated Coaxial Resonators

Abstract

The contribution of this work is to propose a half-mode substrate integrated coaxial resonator (HMSICR) and its application in bandpass filter (BPF) design. The proposed HMSICR is formed by evenly bisecting a square substrate integrated coaxial resonator (SICR), which is a cavity composed of two dielectric substrates and three metal layers. The SICR’s sidewalls are mimicked by periodically spaced thru-via arrays, and a circular patch is embedded in the middle metal layer of the SICR with the patch shorted to the cavity’s bottom wall by a circular array of blind vias. This HMSICR can drastically lower the cavity’s resonance frequency. The achieved frequency reduction rate of the proposed HMSICR, as compared with that of its conventional substrate integrated waveguide (SIW) cavity counterpart, reaches 70%. A sample four-HMSICR BPF is built for the circuit verification measurement. To further reduce the sample filter’s area, the composing HMSICRs are vertically stacked in a back-to-back configuration. We believe that its obtained size-reduction rate reaches the highest record.

Miniaturized Quad-Band Filter Design Using Substrate Integrated Coaxial Cavity

“…In the full-mode cavity of [ 9 ] and the half-mode cavity of [ 12 ], each cavity contains only a resonator and an empirical expression for the resonance frequency can be derived from an equivalent transmission-line model. In our design, although the four resonators are housed in the same cavity, each resonator can still be associated with one equivalent transmission-line model.…”

Novel High-Q Partially Air-Filled Pedestal Resonator and Filter Integrated in a Printed Circuit Board (PCB)

“…Previous works on pedestal SIW resonators presented in [12]- [14], also called mushroom resonator in [15] have demonstrated the possibility to decrease the size of a SIW resonant structure by loading the guide with an intermediate metal plate. In the present work, we propose to combine the advantages of the ESIW (Q-factors) and pedestal topology (compacity) to take benefit of their respective advantages.…”